RCE in Masc-Ucsc Hagent
CVE-2026-117573
hagent through commit 761eec6 contains an OS command injection vulnerability that allows MCP clients to execute shell commands by injecting metacharacters into the args parameter of the hagent_arduino and hagent_esp32 tools. Attackers or prompt-injected agents can supply crafted args interpolated into arduino-cli and idf.py commands run with subprocess.run(shell=True) to execute commands as the MCP server user.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/masc-ucsc/hagent/issues/98 (issue-tracking)
- github.com/masc-ucsc/hagent (product)
- github.com/masc-ucsc/hagent/blob/761eec627a1e6fb128a2a8ce9245aa595cc2f7af/hagen… (technical-description)
- github.com/masc-ucsc/hagent/blob/761eec627a1e6fb128a2a8ce9245aa595cc2f7af/hagen… (technical-description)
- www.vulncheck.com/advisories/hagent-through-commit-761eec6-os-command-injection… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-117573?
- CVE-2026-117573 is a high-severity vulnerability in Masc-Ucsc Hagent, classified under OS Command Injection. CVSS score: 7.8/10. Published 2026-10-27.
- How severe is CVE-2026-117573?
- High severity. CVSS v3 base score is 7.8 out of 10.